Muffler for internal combustion engines



April 16, 1935. H. s. POWELL 1,998,386

MUFFLER FOR INTERNAL COMBUSTION ENGINES Filed March 8, 1953 SWMMW Patented Apr. 16,1935 v 1 993 3 I umrEosT T-ss PATENT OFFICE,"

MUFFLER ma INTERNAL 1 JENGINES 7 Herbert smewen. Utica, ,N. 1. Application Mam-h s; 1933, Serial No. seam Claims ,(01. 137-160) The invention relates to new andk-useful imsimilarly shaped plate at the other side of the" provements in a muiller for expanding gases, and easing which is bent to form spaced walls, with more particularly 'a muiller for internal combusa curved outer end, and the walls are perforated t-ion engines. I in the same manner. These two plates are di- 5 An object of the invention is to provide a mensioned and placed so that the baflles are stag- 5 mufller through which the exhaust gases pass gered, and this produces a sinuous ortortuous in a sinuous path, and wherein there are 'subpath through which the exhaust gases pass stantiallyclosed pockets at each side of the path throughout a greater port-ion of the length of of travel of the gases; into and through which thccasing, The bathe plates are preferably -10 pockets the gases may pass by expansion for respaced away from the receiving end of the cas- 10' ducing the extent of the negative and positive ing so as to'provide an expansion chamber. The impulses incident to the discharge of the exhaust walls of the pockets are flat; and this produces a gases from the engine. relatively thin flat column of; flowing gas.

A further object of the invention is to provide 'It is thought the invention will perhaps be beta mufiler of the above type wherein the walls ter understood by a detail description of the il- 15 constituting the sinuous path are so disposed lustrated "embodiment thereof. The muiller conas to form a relatively thin flat column of flowing sists of a casing l, which as shown, in the drawgases. 1. ing, is circular incross section and the casing is A still further object of the "invention is to elongated to form a relatively long cylindrical :2?) provide a muiller of the above type wherein the casing, receiving the exhaust gases at one end noise incident to the expansion of the gases is thereof and discharging the same from the other silenced in-part by the expansion chamber at end thereof. -At the inletend of the casing there the receiving end of the mu'ifier, in part by the is a partition 2 having aneck portion 3 which is perforated b'afiie plates arrangedto provide the provided with slotsl-andaclamping collar 5 which sinuous path through which the gases pass from encircles theneckportionandisadaptedto clamp 25 the expansion chamber to the outlet end of the the same tothe pipe leading from the engine. At mufiler, and in part by substantially closedpockets the discharge and there is-a partition 8 having a extending into the baffle plates'into and through neck portion 1 provided with slots 8 and a'clanipwhich the exhaust gases expand and pass. ing collar 9 to which the discharge pipe may be 3"; These and other objects will in partbe obvious attached. Within the casing is a plate In. This and will in part be hereinafter more fully displate II is bent so as to providespaced walls ll closed. and I2, which walls are connected at their inner In the drawing which shows by way of illusends by a curved member l3. The walls H and tration one embodiment of the invention 12, including the curved member I3, are provided Figure l is a view in longitudinal cross secwith a'number of small perforations indicated at 35 tion through a muiiier embodying the improve- 1!. It is understood, of course, that these perments; p forations may be varied in size and in number to Fig. 2 is a view of the frontend of the mulller, suit the requirements, The portion Ill of the and s plate I0 is secured tothe inner wall of the casing, 4- Fig. 3 is a sectional view on the line 3-3 of and the walls I'l, Hand 13 form a baffle plate ex- 40 Fig. 1. tending part way across the Within these The improved muffler' or silencer for exhaust walls H, n and I! is a pocket or chamber [5. gases of an internal combustion engine includes The plate I3 is shaped so as to provide a series an elongated casing which may be of any deof these pocketsor baille plates, like the one just Li; sired cross sectional shape. The exhaust gases described. As shown they are all similar in conenter one end of the casing and pass out of the struction and like referenoenumerals have been other end thereof. In the casing is a. plate which applied thereto. The pocketsor bafiles may, howis bent so as to provide spaced walls connected ever, beotherwise shaped and di'lferently shaped by an integral curved section at their-inner ends. at opposite sidesof the mumer. These'baflle plates 51 These walls form pockets and the walls are perhaving the pockets car-chambers therein are spaced 5O forated so that t'hegases moving along the walls from each other and the :portion' of .the plate may pass through the perforations into the between the baflle plates is shown as spaced away pockets. These spaced walls with the connected from the casing, thus providing a small connectcurved ends form a baflle plate, and these baflle ing port l6 joining adjacent pockets or chambers. plates are spaced from each other. There is a The plate I0 is provided with a. portion lo near 55 the discharge end of the casing I, which is secured in any desired way to the casing. There is also a plate i'i formed with parallel walls 18 and 49 with a connected portion 26, which are similar in construction to the walls ll, l2 and [3. There is a pocket between these walls indicated at 2!. There are a series of these bafile plates having pockets or chambers therein, and the walls are all perforated just as described in connection with the walls H and 12. The plate I! has a portion Il which is attached to the casing adjacent the inner end thereof and a portion l'l which is attached to the casing at the outlet end of the casing. This plate H is shaped so as to provide connecting ports 22 of small dimensions between the adjacent pockets. These ports 16 and 22 may be omitted, if desired, so as to provide isolated pockets or chambers in the respective baflles. The plate 51 is so positioned in the casing that the baifle plates formed therein are staggered relative to the baille plates formed in the plate ill. The plates are so dimensioned that there is a relatively short distance between the walls i2 and i8, and also between the walls l9 and H of the next adjacent pocket. This passage bet-ween the plates extends all the way across the casing, and this results in producing a column of gas which is relatively thin and wide, and which travels in a sinuous path between and around the curved ends of the bafiles. The plates l0 and l? are spaced from the partition 2 so as to provide an expansion chamber 23. The gases entering the receiving end of the mufiler are expanded in the chamber 23 and are partly silenced through this releasing of the gases into the chamber which is of much larger diameter than the neck portion 3 at the receiving end of the casing. The passing column of gas will contact with the walls of the bafile plates, and the negative and positive impulses in the gases will cause the gases to flow through these small openings into and out of the pockets or chambers in the bailie plates, thus cushioning and breaking up the regular impulses. Some of the gases will pass through the perforations in the opposite wall of the baffle plate and intercept the flow of the main column of gases, and this aids in the breaking up of the regular impulses and causing an even flow, or nearly so, at the time when the gases reach the end of the muffler. There are three distinct features in the muffler which contribute to the silencing of the noise incident to the release of the exhaust gases through the engine. First, is the chamber 23 into which the gases expand and the regularity in the impulses in part broken up or reduced. Second, the gases pass about the baffles in a sinuous path of travel, which further breaks up the regularity of the impulses and reduces the same. Third, the gases pass through the perforations into the pockets, and as they pass into and out of the pockets, there is a cushioning effect in the expansion of the gases, which again reduces the regular impulses, bringing the same down to a more nearly continuous flow before the gases reach the discharge end of the casing. As noted above, the casing instead of being circular in cross section, may be of any desired shape. The baffle plates may be attached to the casing in any desired way. The invention is not particularly in the details of construction, but rather in the arrangement of the baffle plates so as to provide the pockets and the expansion chamber, all of which contribute to the silencing of the expansion of the gases as they pass through the muffler.

It is obvious therefore, that many changes in the details of construction and the shaping of the parts may be made without departing from the spirit of the invention as set forth in the appended claims.

Having thus described the invention, what I claim as new and desire to secure by letters Patent, is-

1. A mufiler comprising a casing through which the exhaust gases pass, a plate at each side of the casing attached thereto at its ends and shaped intermediate its ends so as to form baflies spaced from each other with the bailles in the respective plates arranged so as to provide a series of communicating substantially U-shaped passages whereby to form a sinuous passage between said battles for the travel of the gases, each baffle consisting of spaced connected perforated walls forming a chamber therein into and through which the gases moving along said walls may pass, said plate being shaped so as to provide ports connecting the adjacent chambers at the respective sides of the casing.

2. A mufiier comprising a casing through which oe exhaust gases pass, bafiles connected to the opposite sides of said casing and arranged to form a sinuous path for the travel of the gases through said casing, each baiile consisting of spaced perforated walls having the inner ends thereof connected whereby to form an unobstructed chamber in which and through which the gases moving along said walls may pass.

3. A mufiler comprising a casing through which the exhaust gases pass, bafiles secured to the casing at opposite sides thereof and arranged to form a sinuous path for the travel of the gases through the casing, each baiile consisting of a substantially U-shaped perforated Wall having the connected end disposed adjacent the center of the casing and forming an unobstructed chamber into which and through which the gases passing along the wall may pass.

i. A mufller comprising a casing through which the exhaust gases pass, plates secured to the casing at opposite sides thereof and each plate being shaped intermediate its ends to provide spaced battles, the bafiles in each plate being arranged to provide a sinuous path for the travel of the gases therebetween, each baffle consisting of spaced perforated walls having the inner ends thereof connected whereby to provide an unobstructed chamber into which and through which the gases moving along said plates may pass.

5. A mufiler comprising a casing through which the exhaust gases pass, plates secured to the easing at opposite sides thereof and each plate being shaped intermediate its ends to provide spaced baffles, the bafiles in each plate being arranged to provide a sinouus path for the travel of the gases therebetween, each baiile consisting of a substantially U-shaped perforated wall having the connected end disposed acjacent the center of the casing and forming an unobstructed chamber into which and through which the gases moving along the wall may pass.

HERBERT S. POWELL. 

